Nigeria's population to double by 2050

The year 2046 will mark an inflexion point when more than half the Indian population will be urban.

Three countries - India, China and Nigeria - will account for 35 percent of the projected growth, with the former adding 416 million urban inhabitants and the latter 189 million.

Not only the most populous city, India is expected to make new records as the most populous country by surpassing China. "It is projected that India will have added 416 million urban dwellers, China 255 million and Nigeria 189 million", said Department of Economic and Social Affairs (DESA) as it announced the findings in NY.

Delhi is expected to overtake Tokyo as the world's largest metropolitan area around 2028, as Japan's population declines and India's continues to grow.

The Guardian reports that while Tokyo is the world's largest city as of now with a population of 37 million people, Delhi follows behind with 29 million residents.

This increased pressure is giving rise to so-called megacities - those with more than 10 million inhabitants.

As of 2018, there are 4.2 billion people living in urban areas worldwide, an enormous increase from the 751 million in 1950.

Today, the most urbanized regions include Northern America (with 82 per cent of its population living in urban areas in 2018), Latin America and the Caribbean (81 per cent), Europe (74 per cent) and Oceania (68 per cent). The level of urbanization in Asia is now approximating 50%. In contrast, Africa remains mostly rural, with 43 per cent of its population living in urban areas.

In contrast, the rural population in the Russian Soviet Federative Socialist Republic (part of the Soviet Union) in 1950 - the year when the United Nations had started collecting statistics-was 57.5 million. This is especially true when it comes to low-income and lower-middle-income countries.

"The increasing concentration of people in cities provides a way of more economically providing services", he said. Globally, fewer cities are projected to see their populations decline from today until 2030, compared to what has occurred during the last two decades. Africa and Asia are home to almost 90 per cent of the world's rural population in 2018. The urbanisation data projected that in 2030 the urban agglomeration of Mumbai will hold on to its rank as the sixth largest with a population of 25 million, up from 19 million in 2015.

Sustainable development, or the successful management of urban growth, is crucial for countries that may face challenges associated with rapid urbanisation, the report suggests.

"When urban growth is rapid, ensuring access to housing, water, sanitation, electricity, public transport, education and health care for all is especially challenging", John Wilmoth, director of the Population Division, said at a United Nations news conference, according to Reuters.